<ngx-echarts [option]="option" [theme]="theme"></ngx-echarts>

<nz-radio-group [(ngModel)]="theme">
  <label nz-radio-button [nzValue]="undefined">default</label>
  <label nz-radio-button nzValue="dark">dark</label>
  <label nz-radio-button [nzValue]="walden">walden</label>
</nz-radio-group>
